This invention relates in general to improvements in distance measuring and indicating devices and deals more specifically with an improved electronic indicating device or instrument for monitoring radial displacement of a rotary member. While the instrument of the present invention may have other uses, it is particularly adapted for use in combination with a computer in an apparatus of the type for calculating the shimming adjustments required to effect accurate coaxial alignment between coupled shafts on associated machines and the like.
Accurate alignment of rotating equipment is essential to prevent wear, minimize vibration, and eliminate premature breakdown. Shaft misalignment is a major cause of machinery component failures involving bearings, seals, gears, couplings and the like. Trial and error shaft aligning methods using feeler gauges, straight edges and the like are well-known in the art. However, these methods are time consuming and often do not produce satisfactory results. Well-known alignment methods utilizing dial indicators in aligning coupled shafts eliminate the need to "break" the coupling between shafts and generally enable a more accurate result. However, the various measurements and mathematical solutions necessary to determine the required machine adjustments to attain shaft alignment are time consuming and prone to human error.
Heretofore, computers of specialized function type have been utilized in conjunction with dial indicators in machine alignment apparatus. A typical computer of the aforedescribed type has appropriate equations stored in a memory for calculating required machine adjustments from measurements taken from the machines and entered in proper sequence in the computer. The Machinery Alignment Analyzer MAC-5 produced by SPM Instrument Inc., Marlborough, Conn., assignee of the present invention, is a typical computer of the aforesaid type.
While such a specialized computer substantially reduces the time required to obtain the necessary mathematical solutions, the accuracy of result is largely dependent upon the accuracy of measurements and readings taken from dial indicators at proper angular positions of shaft rotation and entered in proper sequence into the computer.
It is the general aim of the present invention to provide an improved indicating device or instrument for monitoring the radial displacement of a rotary member, and particularly for use in a shaft aligning apparatus to reduce both the time required to effect shaft alignment and the risk of human error associated with the alignment process.